I'm going to tell the whole story to avoid questions regarding my reasoning:
I am from Brazil. Later last year, a few months before Stormblood was announced, I had the means to purchase FFXIV+HW. The full package through Steam was too expensive at the time (over R$200), so I ended up purchasing the European package (less than R$100 for both ARR and HW).
Besides the price, I also had to consider the fact that I don't have a credit card (banks, at least in my state, require a paycheck to order a credit card, which I can't provide since I'm working as a freelancer). Although the subscription was cheaper through Steam, I was paying a total of R$80-ish for two months at the time for European game time cards, which was reasonable. Over time, the subscription through game time cards became too expensive and I had to stop playing.
With the Steam summer sale and the release of Stormblood, FFXIV became considerably cheaper (R$155.98 for ARR+HW+SB without the 20% discount from the summer sale). The subscription is R$32 a month for the basic plan, which I can afford without a problem since there is a third party service through which I can purchase Steam Wallet credits without a credit card. All that considered, I purchased just the base game through Steam since I didn't want to spend R$150+ right off the bat.
Now, with all that said, I hope I made clear that I have two accounts: one registered as a European account, which I won't be using anymore, and another registered as an NA account through Steam.
I'm not interested in keeping two accounts (there's no reason for that) and I wish I could use my original character name on my home server, but Mog Station doesn't offer an option to delete characters. In short, you have to subscribe to delete a character. I already suspended my European account through Mog Station, but that doesn't make the character names available.
Is there any way I can contact Square Enix through my other account to delete those characters or deactivate the account entirely?